How can I replicate this raised letter effect?
You can use displacement.


Open a movie or image file.

Create a cuboid, stretched along its X-Axis and add an array modifier, duplicating it along the Y-Axis. I choose a relative offset off 2 in the array modifier, this creates gaps between the stripes. In edit mode add a lot of loopcuts along the longest axis, in my case X.

Apply the modifier.
Unwrap it from the top view by pressing U (Unwrap) and choosing Project From View (Bounds). This will unwrap the image exactly as you are currently seeing it in the 3D View. Go to the UV editor and select all. Press . and choose Individual Origins as the Pivot Point. The scale SY the individual islands along Y towards 0. During the scale operation you can type 0 and confirm with &#9166; Enter.

Finally, add a displacement modifier to the arrayed cuboids. Choose Z as the displacement axis and UV for the coordinates.



This results in the displaced geometry.



Consider blurring the movie or image file as a preprocessing step to create smoother transitions.